A pack of cars drives moments before a wreck on the backstretch during NASCAR auto race testing at Daytona International Speedway on Jan. 11, 2013. John Raoux, AP

The car of NASCAR Sprint Cup Series driver Jamie McMurray is towed to the garage after a crash during Preseason Thunder testing at Daytona International Speedway on Jan. 11, 2013. Douglas Jones, USA TODAY Sports

Mark Martin, driver of the No. 55 Toyota, and Jeff Gordon, driver of the No. 24 Chevrolet, lead the field during the NASCAR Sprint Cup Preseason Thunder testing at Daytona International Speedway on Jan. 11, 2013. Tom Pennington, Getty Images

Mark Martin, driver of the No. 55 Toyota, looks on in the garage area during NASCAR Sprint Cup Series Preseason Thunder testing at Daytona International Speedway on Jan. 11, 2013. Jared C. Tilton, Getty Images

Dale Earnhardt Jr. stands by his car in his garage after he started a wreck involving a group of cars during testing at Daytona International Speedway on Jan. 11, 2013. John Raoux, AP

Crew members of NASCAR Sprint Cup Series driver Kyle Busch work on the fender after a crash during Preseason Thunder testing at Daytona International Speedway on Jan. 11, 2013. Douglas Jones, USA TODAY Sports

Michael Waltrip chats with friends in the garage during testing at Daytona International Speedway. Waltrip will enter the Daytona 500 this season driving the No. 30 Toyota for Swan Racing. John Raoux, AP

Ricky Stenhouse Jr. prepares to go out on the track during NASCAR testing at Daytona International Speedway. John Raoux, AP

Rodney Childers, crew chief of the No. 55 Toyota, stands on top of his team hauler during testing at Daytona International Speedway. Jared C. Tilton, Getty Images

A look at Daytona International Speedway as Jimmie Johnson takes off during testing. Jared C. Tilton, Getty Images

A look at Danica Patrick inside her car during testing at Daytona International Speedway. Douglas Jones, USA TODAY Sports

The new Generation 6 NASCAR Sprint Cup cars sit on the grid during testing at Daytona International Speedway Jared C. Tilton, Getty Images

Racing tires are lined up in the garage area at Daytona International Speedway on Jan. 10, 2013, in Daytona Beach, Fla. John Raoux, AP

Driver Joey Logano takes a break in his garage while his crew makes adjustments to his car during NASCAR testing at Daytona International Speedway, Thursday, Jan. 10, 2013, in Daytona Beach, Fla. John Raoux, AP